Leakage testing apparatus



Dec. 25, 1951 Filed sept'. 27, 1945 E. M. HUNT LEAKAGE TESTING APPARATUS 2 SHEETS-SHEET l INVENTOR A EVERETT M. HUNT BYQML M 1 ATTORNEY l Dec. 25, 1951 E M HUNT 2,579,495

LEAKAGE TESTING APPARATUS Filed Sept. 27, 1945 2 SHEETS-SHEET 2 v INVENTOR EVERETT M. HUNT WQWRW ATTORNEY Patented Dec. 25, 1951 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 41883, as amended April 30, 1928; 370 O. G. 757) 2 Claims.

My invention relates to testing apparatus. It has to do, more particularly, with apparatus for testing hollow articles to determine whether or not they are fluid-tight.

It is desirable to test certain articles, such as electric conduit boxes which are used in submarines, to determine whether or not they are fluid-tight. In the past this has been done by a hand method.

The object of this invention is to provide simple but eiective apparatus for readily determining whether or not a hollow article is duid-tight.

The preferred embodiment of my invention is illustrated in the accompanying drawings wherein:

Fig. 1 is a front elevational view, partly cut away, of apparatus constructed in accordance with my invention.

Fig. 2 is an end elevational view, partly cut away, of the apparatus shown in Fig. 1.

Fig. 3 isa bottom plan view taken substantially along line 3--3 of Fig. 1.

Fig. 4 is a perspective view of a portion of the interior of the testing tank and elevator.

Fig. 5 is a perspective view of the box clamping device of my apparatus.

With reference to the drawings I have illustrated my testing apparatus as comprising a liquid tank I (Figs. 1, 2 and 4) formed of.metal and supported by the legs 2. Within the tank I there is mounted a vertically movable elevator 3.

The elevator 3 (Fig. 4) is in the form of a grill composed of longitudinally extending side bars 4 and a middle bar 5 to which a series of transverse bars 8 are welded in longitudinally spaced relationship. The bar 5 projects at each end beyond the main part of the grill to provide a guide I which ts into a vertical guideway 8 formed by a pair of angle irons 9 which are welded to the end ofthe tank I.

The elevator 3 is moved vertically in the tank by means of a cable I attached to each end of the bar by a hook and eye unit Each of the cables I0 passes upwardly around a vertical pulley I2 (Figs. 1 and 2) which is carried by a bracket I3 at a point spaced above the tank I. 'I'he bracket I3 is secured on the upper ends of the angle irons 9 which extend a suiicient distance above the upper edge of the tank. The cable I0 passes downwardly along the end of the tank and then horizontally around a vertical pulley I4. Thev pulley I4 is rotatably supported by a bracket l5 which is attached to the bottom of the tank midway between its side edges. The cable I 0 continues along the bottom of the tank and around a horizontally disposed pulley I6 and its end is connected to a piston rod I'I by means of an eye |84. The two pulleys I6 are carried by a bracket unit I9 which is associated with a, cylindervand piston unit 29 and which includes the piston rod I1.

The unit 20 is carried by a shelf 2| which is secured in spaced relationship to the bottom of the tank and tovwhich the bracket I9 is also secured. This shelf 2| carries a guide or a housing 22 projecting beyond the tank in which the outer end of piston rod I1 reciprocates. Flexible air lines 23 and 24 connect the unit 20 with a suitable control valve 25 which is attached to the tank. A line 26 leads from a suitable source of air under pressure to the valve 25.

It will be apparent that if the unit 2|] is actuated properly by controlling the valve 25, the elevator 3 will be raised and lowered in the tank I through the medium of the connectingoperating cables I0.

As previously indicated, this apparatus is particularly useful for testing electric conduit boxes to determine whether or not they are duid-tight. These boxes usually have one side open or a series of openings in one side. In Fig. 1 I have illustrated, for example, an electric box 21 being tested. y

In order to supportl the electric box to be tested, Iprovide a supporting shelf 28 (Fig. 5) vwhich is welded to the top surfaces of a pair of vertically disposed brackets 29 of rectangular form. These brackets are bolted by means of bolts 30 to the transverse bars of elevator 3. The upper surface of shelf 28 is provided rwith* a compressible pad 3| which is preferably of rubber. and against which the open side of the box is to be clamped.

For clamping the box against the pad 3|, I provide a clamping unit supported by a pair of posts 32. Thelower ends ofA these posts are adjustably threaded into blocks 33 which are secured to the top surface of shelf 28 at the ends thereof. The upper ends of the posts are threaded and slidably receive the sleeves 34 which are secured p to and support a bar 35. The sleeves 34 are posi- 3 clips 38 are of sufcient height to permit limited vertical movement of the plate 31 relative to the bar 35. The plate 31 is normally held in its uppermost position against the bar by means of a spring 4| attached to each of the flanges 4l! of the plate and to the bar 35 adjacent the sleeve 34. For movingthe plate 311 :downwardly :into clamping Arelationshipwith the box; I provide an eccentric 42 which is p-ivoted at 43 to the bar 35 and which engages the upper surface of the This eccentric is actuated by.mea-ns plate 31. of a handle 43.

In using this box supporting and clamping unit, the box is disposed beneath the plate 31 with its open side against the'pad 31. 'Ilfreba'r` I;

35 is adjusted to a suitable height depending on: that of the box. The plate 31 is of such length when it is moved over thebox that the?" flanges 40 will just clear the ends of the box. The: plate 31 is moved downwardlyiagainst the force of the springs 4I by operating the Ahandle 43. The pl'ate- 31-engaging the box 21 tightlyclampsl it against the-pad 3i. Thus, the open side ofthe box will be sealed effectively by the pad 3l'.

`-To`-supply air underpressure within the box, av flexible conduit 44 (Fig. l) is provided which is connected to an outlet openingr45 (Fig. 5f leading through the self 38 and the pad 3lV substantially at the center thereof. This conduit 44 is connectedv to a manifold air line`4-'5 (Fig. l) by a suitable ttingincluding a control valve 41. The manifold 46 is connected by a line 48 toasource of air'under pressure. A control' valve 43 is pro' vided inthe line 43 and a gauge 53 is interposed between the-valve 43 and the nianifol'dlne 46.

A series of the boxf supporting and clamping units may be provided on the elevator 3. These units may be of various sizes to receive various size boxes. Each untwill be connected to the manifold '46 by one ofthe conduits`44.

It will be apparent that in using this apparatus the elevator 3 will be in a raisedposition and the box supporting and clamping units will receive and clamp the boxes. Then the elevator will be lowered so that the boxes will be submerged in the liquid in the tankV l.` Air will be vforced into the boxes and ifanyof the boxes'leak, air bubbles will indicate which of the boxes leak.

The apparatus which I n have provided is a simple but effective apparatus for testing hollov7 articles to determine whether or not they are duide-tight.

The nvention described herein may be manu` yfactured'and used by or'for the Government ci the United States -of America for Government purposes" Without the payment of any` royalty thereon'or therefor.

What l claim is: L In apparatus f0.1 testing hollow articles each having an open side;A aj testing'framecomprising a base plate, a compressible pad carried by said base plate and on which an open side oi one of said articles is adapted to rest, a clamping plate for clamping one of said articles to said pad, said clamping platebeing positioned a predetermined distance above said pad, said clamping plate being movable andresiliently 4biased, away from said pad, guide dmeans for-"maintaining said plate parallel to said pad, a rotatable lever carrying a cam operative to move said clamping plate to secure said.. article between said clamping plate and said pad, and a flexible conduit opening into vsaldi hollowaartcle through said base plate and said, pad.,` said conduit being connected at the other end to 'a source of gas under pressure.

,Y 2'. Apparatus for testing hollow articles each having an open side comprising, in combination, a liquidlled testing tank, an elevator mounted within said tank for vertical movement, said elevator including a supporting frange and a plurality of cables, said cables beingiattached to said frame and extending from said tanl, a cylinder and piston unit supported adiacentsad said cables being connected to said. cylinder and piston unit, meansv for actuating vsaid cylinder and piston unitn4 cause movement Qf, Said. ,elevator. a testine frame Secured to said Supporting frame, said testing frame comprising a hase plate attached to said suppcrtins frame. a @empresse ible pad carried by said base plate. and Vorpvvhich an open side of said articles is caused tovrestr. a clamping platefor clamping said articles t'Qad pad, said clamping plate being positioned apre-. determined distance above said pad, saidciampf. ing plate being movable andresiliently biased awayrfrom said pad, a` rotatable'lever` carrying va cam operative to move said clampingplate tesecure said articlevbetwen Said clamping-plate and said pad, means communicating with the ,interior of said larticle through, saidV pad andl saidbase plate for supplying gas under pressure to the-inf.

teriory of said article, and means'forcontrolling the OW' 0i Said easunder pressure t0 Said artGle when saidarticle is submerged,A in said liquid.

` EYERETT HUNT- circs rifne cllowing/reierences'areof record in the file 0f this patent: l v. v

UNITED STATES PATENTS afnam schmidt .,....'L.-`lf Dec- 1.6.1 15947 

